<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        /*标签基于层叠性会覆盖之前设置的值*/
        p {
            color: red;
            color: blue;
        }
    </style>
</head>
<body>
<p>这是p 标签</p>
</body>
</html>